I recently framed and insulated a new home. I live up here in Manitoba. The temperature is hovering around 32 Farenheit and colder. The house has 1 construction heater for the entire house. [1500 sq.ft.] with full basement. I’ve owned my own remodelling business since 1992 so I’m not new to the work, but this problem I’ve come across is.
The homeowner hired a painter to spray the interior and texture the ceilings. The problem is that in four different locations in the house there are wet areas where the paint has bleeded and dripped. Nothing major. All located where the 8ft wall meets the ceiling. It only happened once while the painting was going on.
I climbed up in the attic and checked our poly and insulation job. Everything looks good. R-20 for walls and R-40 for ceiling, caulked with acoustiseal and 6ml poly.
Its been one week with no repeat of the problem, but the homeowner insists there still is a problem.
I personally think that because of the one heater, there are cold spots on the walls and ceiling and with the high humidity from the spray painting [latex] it condensed on the walls causing the bleeding of the paint. I told the homeowner towait and see what happens after he installs his furnace.
Can anyone shed some light with a similar problem.
Replies
When you say construction heater, is it a propane space heater?
they tend to put alot of moisture into the air. their was a recent post where somebody acutually did the calcs on how much the put out per gallon or pound used.
No. A construction heater is a $80.00 electric heater requiring 240 volts. I think its 1500 watts.
How long was the heat running in house before you started painting. What I'am getting at was house up to a constant temp. before painting commenced.
We didn't do the painting. It was room temperature or warmer wherever the heater was placed. The other rooms were colder [maybe 45-60 F.] depending on the temp. outside. The outside temperature would dip to 15 Farenheit.
Are the soffits and rafter bays clear in these areas. Check the insulation for moisture in these areas.
The air in the room *might* have been sorta warm with that little heater, but I bet the wall being painted was very cold to the touch. Paint doesn't like going onto such a cold surface.
Hi, fellow Manitoban! I have done my own house, painting and texturing as well as a for some clients, and yes, the high humidity of the painting / texturing with the low temp. is what's causing the problem. the extra heat should help as well as getting some air moving in the place, get couple of fans to move the air round a bit and every thing should be fine. Your painter / texture guy should have been aware of this. ( I am a general contractor / carpenter and have been in trade since '91 )
The problem is very high relative humidity (RH) with slightly cooler double top plates due to their lower insulation value. With the RH up in the 70-90% range, the temperature of the wall board at these locations would only have to be a few degrees cooler to encourage condensation from the other paint drying.
Encourage air change in the house by leaving a couple of windows cracked open at all times (another heater may be needed) or open a few windows 2-3-4 times a day for 5 minutes or so to allow a complete air change. The introduced outside air will be only 15-30% RH once warmed. Air does not cost that much to heat (0.018 BTU's per cubic foot versus 1 BTU per lb of water- it's related to the mass) and you will not have cooled the wallboard much with a quick 5 minute air exchange.
You've got to lower and control the humidity and maybe need a bit more heat. The fans moving the air around as previously mentioned will help also.
Hello. Thanks for the reassurance. There is clearly a 2" air space between the insulation and the sheathing. I did tell the homeowner about more circulation. We'll see what happens in the next week or so.